other scenario of "pvmove"

[Stanimir]

Hi!
I need to move ph.extents of lvolume between couple of disks. But I've heard that "pvmove"
is dangerous command. could you offer me another more safety way to do this.
Regards.

[Naveej.K.A]

hi,

pvmove is dangerous as well as slow, when it copies the PEs..

why don't you think of copying using dd, if you are having a similar capacity disks...

dd if=/dev/rdsk/c0t1d0 /dev/rdsk/c0t2d0 bs=1024.

then vgcfgrestore -n /dev/vg02 /dev/rdsk/c0t2d0

with best wishes
Naveej

[Sanjay Kumar Suri]

Why it is dangerous? If the following is taken care pvmove should work.

man pvmove

pvmove succeeds only if there is enough space on the destination physical volumes to hold all the allocated extents of the source physical volume.

sks

[Stanimir]

So I suppose if you use "pvmove" and the telnet-session become broken.

May be something like mirroring...

[Naveej.K.A]

hi,

don't know what will happen if the telnet session breaks....

as a more precautionary measure you can do

nohup pvmove

pvmove is dangerous because, if you interrupt the command, you lose everything.

with best wishes
Naveej

[John Carr_2]

do NOT do anything until you have made a backup. If the pvmove fails you can then restore and restart. play safe.

John.

[Johan Lorimier]

Hi,

I dont have any pb with pvmove, but if dont want to take any risk, and if you have enougth space, use mirror-ux in combination with pvmove. And moreover this can be done online.


Johan

[Naveej.K.A]

hi,

One of the HP documentation about LVM says:

ATTENTION:
pvmove is slow and unsave and therefore not recommended. It is unsafe because it only moves PE by PE, i.e it can be easyly interrupted before completion. Interrupting a pvmove command usually results in a corrupted LV. It is slow because the LVM header gets updated any time a single PE has been moved.

with best wishes
Naveej